HF is a condition in which the heart does not sufficiently pump blood to and from the organs of the body. The American Heart Association estimates that there are approximately six million Americans living with CHF, and there are approximately 53,000 deaths due to CHF each year, making it one of the most significant public health burdens in the United States. As blood is pumped progressively less effectively due to CHF, fluid can aggregate in the legs, a condition called peripheral edema, and in the lungs, a condition called pulmonary edema. Pulmonary edema can cause significant difficulty to breathing, and reduce the effectiveness of breathing in saturating the blood with oxygen. Other symptoms of HF can include cardiac arrhythmias, hypertrophy of the heart muscle, and significant fluid retention and weight gain and subsequent hypertension, also known as high blood pressure. To treat HF, patients may be started on daily regimens of drugs such as antiarrhythmics, antihypertensives, anticoagulants, and diuretics. Diuretics cause an increase in excretion, via urination, of fluid and can thus contribute to reducing the fluid retention that causes hypertension, pulmonary edema, peripheral edema, and low blood oxygen saturation.
The current state of daily monitoring in the home for the effectiveness of treatments is currently limited. The most common methods of monitoring consist of the patient stepping on a bathroom scale every morning to measure his or her body weight. If the patient's weight is significantly higher (approximately 3 pounds higher) than it was on the previous day, it is concluded that the patient is retaining extra fluid and that the dose of diuretic needs to be changed. This method is limited insofar as it only measures one metric. Further, because there are numerous other causes for weight gain, including constipation and consumption of large quantities of food, this method is considered crude and not particularly sensitive. This method of monitoring also provides information only regarding the effectiveness of diuretic therapy and not of other therapies that the patient may be using, and may need to be monitored. It is desirable to provide an at home device that is as user friendly and familiar as a bathroom scale, but provides other significant heart-failure related biometric data. One significant example is monitoring ECG to determine effectiveness of antiarrhythmics. Another example is monitoring the patient's risk of falling, which could pose significant life danger if the patient has taken anticoagulant medication.
As an alternative method to daily weight monitoring, some patients measure blood pressure on a daily basis and report the results. There exists no device that performs a comprehensive analysis of numerous HF-related biometrics in the patient's home and transmits all results instantaneously to the patient's healthcare provider.